Facility Core Summary The Facility Core for Small Molecule Mass Spectrometry (SMMS) is integral to the Center's research mission by enabling high-resolution detection and isolation of halogenated organic compounds (HQCs). This Core does not replicate any analytical services or facilities currently available at the Scripps Institution of Oceanography (SIO). The SMMS Facility Core will be directed by P3 Leader Aluwihare, and technical oversight for the facility will be provided Co-Director Dr. Yongxuan Su. Daily operation and routine maintenance will be the responsibility of Mr. Matthew Woolery. The facility will include several uniquely configured gas chromatography-mass spectrometry (GC-MS) instruments that are intimately integrated with the Center's research mission to identify the suite of HOCs accumulating in the marine environment, discover new HOCs of concern in wildlife and humans, and evaluate environmental sources of HOCs. The overall goal of PI is to identify organisms and habitats of interest with respect to HOC production in the Southern California Bight. A GC Electron Capture Detector (|JECD)/MS capable of screening these samples for relevant HOC production will be available through the Core. Project 2 aims to identify and characterize the prevalence of polybrominated HOC biosynthetic pathways in the marine environment. As such, P2 will rely on the same instrumentation to screen cultures and insure that organisms under investigation are producing compounds of interest. The overall goalof P3 is to identify the suite of small, natural HOCs available to enter human populations through seafood consumption. This research will be supported by the analytical capabilities of two GCXGC instruments integrated into the proposed Facility. The >200 HOCs that bioaccumulate in apex predators and humans cannot be adequately separated from co-eluting compounds for definitive identification and quantification without comprehensive GCXGC separation. To establish the biogenic origin of HOCs of interest, P3 will also conduct stable isotope studies on pure compounds that are isolated from apex predators, purified and concentrated for isotope measurement. A uniquely configured, preparative GCXGC instrument that is included in the Facility will support this research. Two liquid chromatography-mass spectrometry (LC-MS) instruments will also be housed in the Core to analyze fermentation extracts and synthetic organic preparations. The Internal Advisory Committee will discuss Facility business during monthly meetings, and the External Advisory Committee will evaluate the Facility Core for its performance annually.